Cellular communication systems continue to grow in popularity and have become an integral part of both personal and business communications. Cellular telephones and similar devices allow users to place and receive phone calls most anywhere they travel. Moreover, as cellular telephone technology has increased, so too has the functionality of cellular devices. For example, many cellular devices now incorporate Personal Digital Assistant (PDA) features such as calendars, address books, task lists, calculators, memo and writing programs, etc. These multi-function devices usually allow users to send and receive electronic mail (email) messages wirelessly and access the internet via a cellular network and/or a wireless local area network (WLAN), for example.
Some cellular devices incorporate contactless card technology and/or Near Field Communication chips. Near Field Communication technology is commonly used for contactless short-range communications based on radio frequency identification (RFID) standards, using magnetic field induction to enable communication between electronic devices, including mobile wireless communications devices. These short-range applications include payment and ticketing, electronic keys, identification, device set-up service and similar information sharing. This short-range high frequency wireless communication technology exchanges data between devices over a short distance, such as only a few centimeters.
Near Field Communication (NFC) technology is an extension of the ISO 14443 proximity-card standard as a contactless card, RF ID standard that incorporates the interface of a smart card and a reader into one device. A NFC device such as a mobile phone typically includes an NFC integrated circuit (IC) chip that communicates with both existing ISO 14443 smart cards and readers and other NFC devices and compatible with any existing contactless infrastructure. The NFC IC chips use magnetic field induction where two loop antennas are located near each other and form an air-core transformer. The technology operates on the unlicensed radio frequency ISM band of about 13.56 MHz and has a bandwidth of about 2 MHz. The working distance is usually about 0 to 20 centimeters and a user of the NFC device touches another NFC device or tag to initiate communication, with data rates ranging from 106 to about 424 kbit/s. Most mobile wireless communications devices operate in an active communications mode using a modified Miller and 100% amplitude shift keyed (ASK) code unless a passive mode is used in which a Manchester and ASK code is used. Further details are set forth in the Mobile NFC Technical Guidelines, Version 2.0, November 2007 by GSMA, the disclosure which is hereby incorporated by reference in its entirety.